SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4c102f7aa2113bcc9759ad490b75fb6e3b10a842301dce2585f04a4b5cec26e1' 
  AND token = 'eFwLrmQHO/q6ylo/aTR8QArLLDVfbFekwxUdaW5AV7Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}